Brazing components and techniques

ABSTRACT

A method of joining includes applying braze to a braze reservoir in a first component. A second component is engaged to the first component, wherein a joint location is defined between the first and second components. A wicking structure provides flow communication from the braze reservoir to the joint location. The method also includes joining the first and second components together at the joint location by applying heat to the braze to flow the braze from the reservoir through the wicking structure to the joint location to form a braze joint at the joint location.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present disclosure relates to joining techniques, and moreparticularly to brazing such as used in joining metallic components.

2. Description of Related Art

Conventional construction of fuel injectors, nozzles, and atomizersincludes components bonded together by braze. The components have milledslots or drilled holes to control the flow of fuel and prepare the fuelfor atomization. The components are typically nested within one anotherand form a narrow diametral gap which is filled with a braze alloy. Thebraze alloy is applied as a braze paste, wire ring, or as a thin sheetshim on the external surfaces or within pockets inside the assembly. Theassembly is then heated and the braze alloy melts and flows into thenarrow diametral gap and securely bonds the components together uponcooling.

Such conventional methods and systems generally have been consideredsatisfactory for their intended purpose. However, when using traditionalbrazing techniques, the braze alloy must flow from a ring or pocket tothe braze area. In doing so, it is prone to flow imprecisely whenmelted. It is also not uncommon for braze fillets to be formed on or incertain features. In some instances intricate or narrow passages canbecome plugged if too much braze is used. These fillets and plugs cannegatively affect nozzle performance. Moreover, braze may not flow tothe desired braze area in the quantity needed to ensure a proper brazejoint. This is typical when the braze alloy cannot be located in closeproximity to the desired braze joint location.

The difficulty in controlling braze flow employing traditional brazingtechniques is a limiting factor in the design of fuel and air flowpassages within a nozzle. That is, the shape and size of the flowpassages is limited by the ability to control the flow of braze.

Such conventional methods and systems have generally been consideredsatisfactory for their intended purpose. However, there is still a needin the art for improved brazing. The present disclosure provides asolution for this need.

SUMMARY OF THE INVENTION

A method of joining includes applying braze to a braze reservoir in afirst component. A second component is engaged to the first component,wherein a joint location is defined between the first and secondcomponents. A wicking structure provides flow communication from thebraze reservoir to the joint location. The method also includes joiningthe first and second components together at the joint location byapplying heat to the braze to flow the braze from the reservoir throughthe wicking structure to the joint location to form a braze joint at thejoint location.

Engaging the second component to the first component can includeengaging the second component to the first component with the wickingstructure between the first and second components. The first componentcan be radially nested with the second component, wherein the wickingstructure is radially between the first and second components, andwherein the joint location and the braze reservoir are axially spacedapart.

The first component can include a radial vane, wherein the wickingstructure extends radially through the radial vane, and wherein joiningthe first and second components includes flowing the braze radiallyoutward to the joint location, wherein the joint location is at an endof the radial vane.

There can be a gap between the first and second components on eitherside of the braze reservoir after the first and second components areengaged, wherein the wicking structure and the joint location are on oneside of the braze reservoir, and wherein joining includes flowing thebraze into the wicking structure to the joint location leaving the gapon the side of the braze reservoir opposite the wicking structuresubstantially devoid of braze. It is also contemplated that there can bea gap between the first and second components adjacent the wickingstructure when the first and second components are engaged, whereinjoining includes flowing the braze into the wicking structure to thejoint location leaving the gap substantially devoid of braze.

A nozzle includes a first nozzle component and a second nozzle componentjoined to the first nozzle component at a joint location. A wickingstructure extends from a braze reservoir defined in the first nozzlecomponent to the joint location.

The first and second nozzle components can be radially nested, whereinthe wicking structure is radially between the first and second nozzlecomponents, and wherein the joint location and the braze reservoir areaxially spaced apart. The wicking structure can be integral with thefirst nozzle component. The wicking structure can include a repeatingpattern, a semi-sintered material, or a woven material. The wickingstructure can be additively manufactured, e.g., as part of at least oneof the first or second components.

These and other features of the systems and methods of the subjectdisclosure will become more readily apparent to those skilled in the artfrom the following detailed description of the preferred embodimentstaken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those skilled in the art to which the subject disclosureappertains will readily understand how to make and use the devices andmethods of the subject disclosure without undue experimentation,preferred embodiments thereof will be described in detail herein belowwith reference to certain figures, wherein:

FIG. 1 is a cross-sectional perspective view of an exemplary embodimentof a nozzle component constructed in accordance with the presentdisclosure, showing a wicking structure extending radially through aswirler vane;

FIG. 2 is a cross-sectional perspective view of the nozzle component ofFIG. 1, showing a second nozzle component being joined to the firstnozzle component;

FIG. 3 is a cross-sectional perspective view of a nozzle constructed inaccordance with the present disclosure, showing two nozzle componentsbeing joined using multiple wicking structures;

FIG. 4 is a cross-sectional perspective view of a portion of the nozzleof FIG. 3, schematically showing the flow of braze through the wickingstructure to a joint location and away from a gap that is intended to bekept clear of braze;

FIG. 5 is a cross-sectional perspective view of a portion of the nozzleof FIG. 3, schematically showing the flow of braze in two wickingstructures to joint locations while keeping a flow passage clear ofbraze;

FIG. 6 is a plan view of an exemplary wicking structure in accordancewith the present disclosure, showing a regular, woven pattern;

FIG. 7 is a plan view of an exemplary wicking structure in accordancewith the present disclosure, showing an irregular, semi-sinteredpattern; and

FIG. 8 is a cross-sectional perspective view of an exemplary embodimentof a wicking structure in accordance with the present disclosure,showing a regular, repeating pattern.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made to the drawings wherein like referencenumerals identify similar structural features or aspects of the subjectdisclosure. For purposes of explanation and illustration, and notlimitation, a partial view of an exemplary embodiment of a portion of anozzle in accordance with the disclosure is shown in FIG. 1 and isdesignated generally by reference character 100. Other embodiments ofnozzles in accordance with the disclosure, or aspects thereof, areprovided in FIGS. 2-8, as will be described. The systems and methodsdescribed herein can be used to improve control of braze flow whenbrazing components together.

This disclosure describes techniques in brazing using the exemplarycontext of joining nozzle components, such as used in gas turbineengines. However, those skilled in the art will readily appreciate thatbrazing techniques as disclosed herein can be used to join any suitablecomponents without departing from the scope of this disclosure.

A nozzle 100 includes a first nozzle component 102 and a second nozzlecomponent 104 (shown in FIG. 2) joined to the first nozzle component 102at a joint location 106. A wicking structure 108 extends from a brazereservoir 110 defined in the first nozzle component 102 to the jointlocation 106. A braze ring 112, braze paste, or any other suitable formof braze is seated in the braze reservoir 110.

Referring now to FIG. 2, the first and second nozzle components 102 and104 are radially nested when assembled. A method of joining includesapplying braze, e.g., braze ring 112 to a braze reservoir, e.g., brazereservoir 110 in a first component, e.g., first component 102. A secondcomponent, e.g., second component 104, is engaged to the firstcomponent. A joint location, e.g. joint location 106 shown in FIG. 1, isdefined between the first and second components. A wicking structure,e.g., wicking structure 108, provides flow communication from the brazereservoir to the joint location. The method also includes joining thefirst and second components together at the joint location by applyingheat to the braze to flow the braze from the reservoir through thewicking structure to the joint location to form a braze joint at thejoint location. In FIG. 2, the flow of braze radially outward isindicated by the flow arrows in wicking structure 108, and in FIG. 1,the flow of braze along joint location 106 is indicated by the arrows onjoint location 106. In this example, the first component 102 canincludes a radial vane 114, wherein the wicking structure 108 extendsradially through the radial vane 114. In this example, joining the firstand second components 102 and 104 includes flowing the braze radiallyoutward from the braze reservoir 110 to the joint location 106, whereinthe joint location 106 is at an end of the radial vane 114. Each vane114 that requires a braze joint can include a similar wicking structure108. The wicking structure 108 can remain a part of the final nozzleafter the brazing is complete.

With reference now to FIG. 3, another exemplary embodiment of a nozzle200 is shown with the first component 202 radially nested within thesecond component 204. Engaging the second component 204 to the firstcomponent 202 includes engaging the second component 204 to the firstcomponent 202 with the wicking structure 208 between the first andsecond components 202 and 204. In FIG. 3 there are three wickingstructures 208 that are each radially between the first and secondnozzle components 202 and 204.

With reference to FIG. 4, the joint location 206 and the braze reservoir210 are axially spaced apart, e.g., in the direction of axis A labeledin FIG. 3. After the first and second components 202 and 204 are engagedthere is a gap 216 radially between the first and second components 202and 204 on either side of the braze reservoir 210 axially. Gap 216 canbe small, such as 0.001 to 0.002 inches (0.254 mm to 0.508 mm). Thewicking structure 208 and the joint location 206 are on one side of thebraze reservoir 210 axially. In this example, joining the first andsecond components 202 and 204 includes flowing the braze 212 into thewicking structure 208 to the joint location 206 leaving the gap 216 onthe side of the braze reservoir 210 opposite the wicking structure 208substantially devoid of braze after the brazing is completed. Referringto FIG. 5, it is also contemplated that there can be a gap 218, e.g., afunctional fuel passage in a nozzle that is not to be plugged withbraze, between the first and second components 202 and 204 adjacent thetwo wicking structures 208 when the first and second components 202 and204 are engaged. In this example, joining the first and secondcomponents 202 and 204 includes flowing the braze 212 into the wickingstructures 208 to the joint location 208 while leaving the gap 218substantially devoid of braze. In the example in FIG. 5, the brazereservoir 210 is defined in the second component 204, and the braze flowis indicated schematically in the axial direction for the wickingstructure 208 on the right in FIG. 5.

With reference now to FIG. 6, the wicking structure 308, which can beused in place of wicking structures 108 or 208, can include a repeatingpattern and can be separately manufactured and added to one of thecomponents, e.g., components 202 or 204. The wicking structure 308includes a weave of metallic wires. In FIG. 7, another exemplary wickingstructure 408 is shown, which can be made integral with the first orsecond nozzle component, e.g., using additive manufacturing. Wickingstructure 408 includes a semi-sintered material that forms an irregularor random pattern. FIG. 8 shows another example of a wicking structure508 that forms a regular, repeating pattern to draw braze 512 in theaxial direction indicated by the large arrow in FIG. 8. Those skilled inthe art will readily appreciate that any other suitable wickingstructure, e.g., a reticulated material, can be used to provide wickingor capillary action for molten braze during the brazing process toconvey molten braze to a braze joint location. This provides bettercontrol so that braze flows where it is intended to flow, even inintricate parts traditionally too intricate for using braze. It is alsopossible with systems and methods as disclosed herein to locate thebraze reservoir remotely from where the braze joint is located whichprovides additional design flexibility compared to traditionaltechniques.

The methods and systems of the present disclosure, as described aboveand shown in the drawings, provide for brazing with superior propertiesincluding improved control over the flow of braze during the brazingprocess compared to traditional techniques. While the apparatus andmethods of the subject disclosure have been shown and described withreference to preferred embodiments, those skilled in the art willreadily appreciate that changes and/or modifications may be made theretowithout departing from the scope of the subject disclosure.

What is claimed is:
 1. A method of joining comprising: applying braze toa braze reservoir in a first component; engaging a second component tothe first component, wherein a joint location is defined between thefirst and second components, wherein a wicking structure provides flowcommunication from the braze reservoir to the joint location; heatingthe braze; flowing the braze from the reservoir through the wickingstructure to the joint location; and joining the first and secondcomponents together.
 2. A method as recited in claim 1, wherein engagingthe second component to the first component includes engaging the secondcomponent to the first component with the wicking structure between thefirst and second components.
 3. A method as recited in claim 1, whereinengaging the second component to the first component includes engagingthe second component to the first component with the first and secondcomponents are radially nested, wherein the wicking structure isradially between the first and second components, and wherein the jointlocation and the braze reservoir are axially spaced apart.
 4. A methodas recited in claim 1, wherein the first component includes a radialvane, wherein the wicking structure extends radially through the radialvane, and wherein joining the first and second components includesflowing the braze radially outward to the joint location, wherein thejoint location is at an end of the radial vane.
 5. A method as recitedin claim 1, wherein there is a gap between the first and secondcomponents on either side of the braze reservoir after the first andsecond components are engaged, wherein the wicking structure and thejoint location are on one side of the braze reservoir, and whereinjoining includes flowing the braze into the wicking structure to thejoint location leaving the gap on the side of the braze reservoiropposite the wicking structure substantially devoid of braze.
 6. Amethod as recited in claim 1, wherein there is a gap between the firstand second components adjacent the wicking structure when the first andsecond components are engaged, wherein joining includes flowing thebraze into the wicking structure to the joint location leaving the gapsubstantially devoid of braze.
 7. A nozzle comprising: a first nozzlecomponent; a second nozzle component joined to the first nozzlecomponent at a joint location; and a wicking structure extending from abraze reservoir to the joint location, wherein the braze reservoir isdefined in the first nozzle component.
 8. A nozzle as recited in claim7, wherein the wicking structure and a braze joint are between the firstand second nozzle components.
 9. A nozzle as recited in claim 7, whereinthe first and second nozzle components are radially nested, wherein thewicking structure is radially between the first and second nozzlecomponents, and wherein the joint location and the braze reservoir areaxially spaced apart.
 10. A nozzle as recited in claim 7, wherein thefirst nozzle component includes a radial vane, wherein the wickingstructure extends radially through the radial vane, and wherein thejoint location is at an end of the radial vane.
 11. A nozzle as recitedin claim 7, wherein there is a gap between the first and second nozzlecomponents on either side of the braze reservoir, wherein the wickingstructure and the joint location are on one side of the braze reservoir,and wherein the gap on the side of the braze reservoir opposite thewicking structure is substantially devoid of braze.
 12. A nozzle asrecited in claim 7, wherein there is a gap between the first and secondnozzle components adjacent the wicking structure, wherein the gap issubstantially devoid of braze.
 13. A nozzle as recited in claim 7,wherein the wicking structure is integral with the first nozzlecomponent.
 14. A nozzle as recited in claim 13, wherein the wickingstructure includes a repeating pattern.
 15. A nozzle as recited in claim7, wherein the wicking structure includes a semi-sintered material. 16.A nozzle as recited in claim 7, wherein the wicking structure includes awoven material.
 17. A method of making a braze joint comprising:applying braze to a braze reservoir in a first component; engaging asecond component to the first component, wherein a joint location isdefined between the first and second components, wherein a wickingstructure provides flow communication from the braze reservoir to thejoint location; heating the braze; flowing the braze from the reservoirthrough the wicking structure to the joint location; and joining thefirst and second components together.
 18. A method as recited in claim17, further comprising additively manufacturing the wicking structure.19. A method as recited in claim 18, wherein the wicking structure isadditively manufactured as part of at least one of the first or secondcomponents.